1. Field of the Invention
The present invention generally relates to wireless data communications techniques, and in particular to a communication protocol for a wireless data communication device supporting at least non-connection data communication.
2. Description of the Related Art
As a communication protocol, connection and non-connection communication protocols have been known. In the connection communication protocol, one party identifies another party to communicate with before communicating with the identified party, which is called xe2x80x9cConnection Writexe2x80x9d in the IrMC (Infrared Mobile Communications) standard (see xe2x80x9cTelecom Specificationxe2x80x9d). The IrMC standard has been introduced by the Infrared Data Association (IrDA), defining common data exchange formats and protocols for interoperability in mobile communications devices such as a mobile telephone, a mobile personal computer, and the like. In the non-connection communication protocol, on the other hand, the one party transmits data to another party in only one direction without identifying the destination, which is called xe2x80x9cUltra Writexe2x80x9d in the IrMC standard.
A mobile communication device having the infrared communication function as mentioned above alternately performs ON-LINE operation (search mode) and OFF-LINE operation (off mode) in a predetermined period. More specifically, in the search mode, the device transmits a Query signal for informing another device of its own information such as device name, and then changes into normal discovery mode (NDM) to wait for a Query signal to be received from another device. According to IrMC standard, the Query signal is supposed to be consecutively transmitted three times before the NDM.
When receiving a Ouery signal from another device during the NDM period, the device determines whether the other device is permitted to be connected. If permitted, a connection request signal is transmitted to the other device or it may be received from the other device. Since the Auto-Find-IAS of a mobile communication device conforming to the IrMC standard defaults to xe2x80x9cEnablexe2x80x9d, the IAS (Information Access Service) search is automatically started when receiving the connection request signal from the other device. In other words, upon reception of the connection request, the device automatically and periodically transmits IAS to the other device to determine whether communication can be established between them.
According to the non-connection communication protocol, however, the non-connection communication cannot be performed during the ON-LINE operation. Therefore, as shown in FIG. 4B, when a non-connection communication request occurs during the ON-LINE operation, an error state is generated and thereby the non-connection communication is not permitted until the ON-LINE operation has been completed.
Further, in the case where the device has been discovered by the other device receiving the Query signal transmitted by the device, the device automatically transmits the IAS to the other device when receiving the connected request from the other device. Therefore, even if the other device is an undesired device to communicate with, the IAS is automatically transmitted to the other device.
An object of the present invention is to provide a wireless non-connection data communication apparatus and a control method therefor, which can promptly respond to a non-connection communication request.
Another object of the present invention is to provide a wireless non-connection data communication apparatus and a control method therefor, which can ensure security in communications.
According to the present invention, a control method for a wireless communication device which has an online mode and an offline mode and supports at least non-connection communication which is allowed in the offline mode, comprises the steps of: a) determining whether a request for the non-connection communication occurs; b) when the communication request occurs during the online mode, changing the online mode to the offline mode in response to occurrence of the communication request; and c) starting the non-connection communication.
When a non-connection communication request occurs during connection communication with another wireless communication device, it is preferably that the connection communication is disconnected and the non-connection communication is started in response to the non-connection communication request.
According to anther aspect of the present invention, a control method for the wireless communication device comprises the steps of: a) determining whether a request for the non-connection communication occurs; b) when the communication request occurs, setting a communication mode to a no-response mode in response to occurrence of the communication request, wherein the no-response mode provides no response to a request received from another communication device; c) when the communication request occurs during the online mode, changing the online mode to the offline mode in response to occurrence of the communication request; and d) starting the non-connection communication.
The no-response mode may be set by disabling an Auto-Find-IAS function conforming to IrMC (Infrared Mobile Communications) standard.
Since the online operation is halted when the non-connection communication request occurs, the non-connection communication can be promptly started, resulting in reduced power consumption.
Further, since the apparatus is set to the no-response mode in response to the non-connection communication request, undesired connection can be prevented, resulting in Improved security.